Bhagavad Gita Chapter 13.31
yadā bhūta-pṛthag-bhāvam
eka-stham anupaśyati
tata eva ca vistāraḿ
brahma sampadyate tadā
Translation
When a sensible man ceases to see different identities due to different material bodies and he sees how beings are expanded everywhere, he attains to the Brahman conception.